中文
相关论文

相关论文: Empirically Derived Integrated Stellar Yields of F…

200 篇论文

We propose a semi-analytic model that is developed to understand the cosmological evolution of the mean metallicity in the Universe. In particular, we study the contributions of Population III (Pop III) and Population II (Pop II) stars to…

宇宙学与河外天体物理 · 物理学 2022-12-21 Lia C. Corazza , Oswaldo D. Miranda , Carlos A. Wuensche

CONTEXT:The detailed chemical abundances of extremely metal-poor (EMP) stars are key guides to understanding the early chemical evolution of the Galaxy. Most existing data are, however, for giant stars which may have experienced internal…

The atmospheric parameters and abundances of Mg, Si, Ca, and Ti have been determined for 20 stars using the Gaia DR2 parallaxes, high-resolution spectra, and the non-local thermodynamic equilibrium (non-LTE) line formation modeling. A…

太阳与恒星天体物理 · 物理学 2019-09-04 Lyudmila Mashonkina , Maria Neretina , Tatyana Sitnova , Yuri Pakhomov

Abundances of five elements, Na, Mg, Al, Si, and Sr, are investigated for 44 very metal-poor stars (-4.0 < [Fe/H] < -1.5) in the Galactic halo system based on an Local Thermodinamic Equilibrium (LTE) analysis of high-resolution…

It is still being debated whether the well-known metallicity - giant planet correlation for dwarf stars is also valid for giant stars. For this reason, having precise metallicities is very important. Different methods can provide different…

地球与行星天体物理 · 物理学 2015-06-16 A. Mortier , N. C. Santos , S. G. Sousa , V. Zh. Adibekyan , E. Delgado Mena , M. Tsantaki , G. Israelian , M. Mayor

The elemental abundances of symbiotic giants are essential to address the role of chemical composition in the evolution of symbiotic binaries, to map their parent population, and to trace their mass transfer history. However, the number of…

太阳与恒星天体物理 · 物理学 2015-11-16 Cezary Galan , Joanna Mikolajewska , Kenneth H. Hinkle , Richard R. Joyce

We present new ultra-metal-poor (UMP) stars parameters with [Fe/H]<-4.0 based on line-by-line non-local thermodynamic equilibrium (NLTE) abundances using an up-to-date iron model atom with a new recipe for non-elastic hydrogen collision…

太阳与恒星天体物理 · 物理学 2017-10-11 Rana Ezzeddine , Anna Frebel , Bertrand Plez

We present results for the evolution of the abundances of heavy elements (O, Mg, Al, Si, K, Ca, Cr, Mn, Ni and Fe) in the inner Galactic regions ($R_{GC} < 4$kpc). We adopt a detailed chemical evolution model already tested for the Galactic…

星系天体物理 · 物理学 2020-05-06 F. Matteucci , A. Vasini , V. Grisoni , M. Schultheis

The diagram depicting the abundance ratios [Mg/Mn] vs. [Al/Fe] has gained attention in recent literature as a valuable tool for exploring fundamental aspects of the evolution of the Milky Way and the Local Group. In particular, this…

星系天体物理 · 物理学 2023-10-10 Arianna Vasini , Emanuele Spitoni , Francesca Matteucci

We use integrated-light spectroscopic observations to measure metallicities and chemical abundances for two extragalactic young massive star clusters (NGC1313-379 and NGC1705-1). The spectra were obtained with the X-Shooter spectrograph on…

星系天体物理 · 物理学 2017-07-19 Svea Hernandez , Søren Larsen , Scott Trager , Paul Groot

Integrated light from distant galaxies is often compared to stellar population models via the equivalent widths of spectral features--spectral indices--whose strengths rely on the abundances of one or more elements. Such comparisons hinge…

天体物理学 · 物理学 2009-06-23 A. Dotter , B. Chaboyer , J. W. Ferguson , H. -c. Lee , G. Worthey , E. Baron , D. Jevremovic

We present new nucleosynthesis yields as functions of the stellar mass, metallicity, and explosion energy (corresponding to normal supernovae and Hypernovae). We apply the results to the chemical evolution of the solar neighborhood. Our new…

天体物理学 · 物理学 2011-05-05 Ken'ichi Nomoto , Nozomu Tominaga , Hideyuki Umeda , Chiaki Kobayashi , Keiichi Maeda

We propose and apply a new classification for the CEMP-no stars, which are "carbon-enhanced metal-poor" stars with no overabundance of s-elements and with [Fe/H] generally inferior or equal to -2.5. This classification is based on the…

太阳与恒星天体物理 · 物理学 2015-07-29 Andre Maeder , Georges Meynet

We compare elemental abundance patterns of $\sim 200$ extremely metal-poor (EMP; [Fe/H]$<-3$) stars with supernova yields of metal-free stars in order to obtain insights into the characteristic masses of the first (Population III or Pop…

太阳与恒星天体物理 · 物理学 2018-04-25 Miho N. Ishigaki , Nozomu Tominaga , Chiaki Kobayashi , Ken'ichi Nomoto

We derive empirical constraints on the nucleosynthetic yields of nitrogen by incorporating N enrichment into our previously developed and empirically tuned multi-zone galactic chemical evolution model. We adopt a metallicity-independent…

星系天体物理 · 物理学 2023-02-01 James W. Johnson , David H. Weinberg , Fiorenzo Vincenzo , Jonathan C. Bird , Emily J. Griffith

Low-metallicity stars preserve the signatures of the first stellar nucleosynthesis events in the Galaxy, as their surface abundances reflect the composition of the interstellar medium from which they were born. Aside from primordial Big…

太阳与恒星天体物理 · 物理学 2025-03-25 Khalil Farouqi , Anna Frebel , Friedrich-Karl Thielemann

We provide a set of stellar evolution and nucleosynthesis calculations that applies established physics assumptions simultaneously to low- and intermediate-mass and massive star models. Our goal is to provide an internally consistent and…

We find that hot jupiter host stars within the T$_\mathrm{eff}$ range 5900-6300K show lower Li abundances, by 0.14 dex, than stars without detected planets. This offset has a significance at the level 7$\sigma$, pointing to a stronger…

We have analyzed high-resolution and high signal-to-noise ratio optical spectra of nearby FGK stars with and without detected giant planets in order to homogeneously measure their photospheric parameters, mass, age, and the abundances of…

太阳与恒星天体物理 · 物理学 2015-07-29 R. da Silva , A. C. Milone , H. J. Rocha-Pinto

Gaseous and stellar metallicities in galaxies are nowadays routinely used to constrain the evolutionary processes in galaxies. This requires the knowledge of the average yield per stellar generation, $y_{\text{Z}}$, i.e. the quantity of…

星系天体物理 · 物理学 2015-12-16 Fiorenzo Vincenzo , Francesca Matteucci , Francesco Belfiore , Roberto Maiolino